A solution of 3-cyanophenylboronic acid (4.74 g), (S)-tert-butyl 1-cyano-2-(4-iodophenyl)ethylcarbamate (10 g) and bis[bis(1,2-diphenylphosphino)-ethane]palladium (0) (0.243 g) in dioxane (100 mL) under nitrogen, was stirred for 10 min. A solution of potassium carbonate (7.43 g) in water (30 mL) was added and the resulting solution was stirred at 75° C. for 3 h. The cooled mixture was poured into water containing brine and extracted with ethyl acetate (3×150 mL). The combined organics were washed with saturated brine (3×50 mL), dried over sodium sulfate and adsorbed onto silica. The crude product was purified by flash silica chromatography, eluting with 20% ethyl acetate in isohexane. Pure fractions were evaporated to dryness to afford (S)-tert-butyl 1-cyano-2-(3′-cyanobiphenyl-4-yl)ethylcarbamate (8.42 g) as a pale yellow solid.
